Clip connector terminal for insulated conductors

ABSTRACT

The terminal element of a clip connector for insulated conductors includes a centrally positioned, upstanding, sharpedged contact blade surrounded by a resilient wire yoke, each leg of which forms with an adjacent edge of said blade a clamping gap into which a conductor is forced by a pusher slide which, in turn, locks in place on said terminal element. As the conductor is forced into said clamping gap, the insulation of the conductor is penetrated by metal parts forming said clamping gap. An electric contact of permanent pressure is established.

United States Patent Inventors Heinz Krone;

Joachim Rott; Horst Hahn; Lothar Zerrenner, all of Berlin, Germany Appl. No. 833,024 Filed June 13, 1969 Patented Oct. 5, 1971 Assignee Krone Kommanditgesellschaft Berlin, Germany Priority June 14, 1968 Germany P 17 65 584.4

CLIP CONNECTOR TERMINAL FOR INSULATED CONDUCTORS 3 Claims, 10 Drawing Figs.

US. Cl 339/97 R Int. Cl Holr 9/08 Field of Search 339/97-99 [56] References Cited UNITED STATES PATENTS 3,132,913 5/1964 Pohl 339/97 P 3,380,013 4/1968 Krone et a1. 339/97 P FOREIGN PATENTS 1,413,504 8/1965 France 339/97 Primary Examiner-Joseph H. McGlynn Attorney-Edwin E. Greigg ABSTRACT: The terminal element of a clip connector for insulated conductors includes a centrally positioned, upstanding, sharp-edged contact blade surrounded by a resilient wire yoke, each leg of which forms with an adjacent edge of said blade a clamping gap into which a conductor is forced by a pusher slide which, in turn, locks in place on said terminal element. As the conductor is forced into said clamping gap, the insulation of the conductor is penetrated by metal parts forming said clamping gap. An electric contact of permanent pres- .sete t io bs-w PATENTEUOBI Si n 3611.263

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H0)?! ISM/IN BY g 6 ATTORNEY CLIP CONNECTOR TERMINAL FOR INSULATED CONDUCTORS BACKGROUND OF THE INVENTION This invention relates to a clamp-type connector to establish an electric connection between one or two insulated conductors on the one hand and a terminal element on the other hand.

In known electric clip connectors the insulated wire is positioned in slotted parts (clamping gaps) of the terminal element and, by a pushermember or the like, usually forming part of the connector, they are pressed into the slot. Further, clip connectors are known in which the terminal element has two spaced slots into each of which a conductor is pressed. Designs of this type are in general too voluminous for particular applications and their capability to ensure a secure contact, which depends on the design of the slots in the terminal element, is limited.

A satisfactory clamping connection performed by clip connectors depends on the magnitude of the area of contact between the terminal element and the metal wire and a continuous contact pressure exerted on the wire conductor by the clamping parts.

It was found that in known slotted terminal elements the aforenoted contact pressure weakens after a certain period of use since metal fatigue, appearing in most leaflike terminal elements, affects the resilient properties of the clamping parts. Thus, as the contact pressure decreases, the contact resistance (which is the measure of areliable contact) increases. As a result, clip connectors of this type are regarded as only conditionally secure for a longer period of use.

Further, significant decrease in the contact pressure may appear in known clip connectors where two conductors are disposed in a superimposed manner in the same slot of the terminal element and, for some reason, the lower wire has to be replaced. In such a case the clamping connection of the upper wire has also to be loosened. It is apparent that when the clip is closed anew, the contact pressure in the slot will be smaller than that obtained upon the first closing operation.

OBJECT, SUMMARY AND ADVANTAGE OF THE INVENTION It is an object of the invention to provide an improved electrical clip connector of the aforenoted type wherein the terminal element is of reduced volume, is simple to manufacture and provides a permanent contact pressure even in case where two conductor wires are clamped by the clip and the latter has to be opened and closed anew for replacing the wires.

Briefly stated, according to the invention, at least one side of two clamping gaps provided in the terminal element of the clip connector is formed of a leg of a resilient wire yoke and the other side of each of said clamping gaps is formed either by a sharp-edged contact element or again by a leg of a resilient wire yoke. A conductor is forced into each clamping gap by a pusher slide which subsequently locks in place and reinforces, as well as stabilizes, the contact pressure exerted on the conductor. v

The principal advantage of the aforeoutlined structure is the provision of a permanent contact pressure of the springing wire yoke legs exerted on the conductors engaged in separate clamping gaps.

The invention will be better understood, as well as further objects and advantages will become more apparent, from the ensuing detailed specification of two exemplary embodiments of the invention taken in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a perspective view of a first embodiment of the invention in an open position;

FIG. 2 is a perspective view of the same embodiment shown in a closed position and clamping a sole conductor;

FIG. 3 is a perspective view of the same embodiment shown in a closed position and clamping two conductors;

FIG. 4 is a front elevational view of the same embodiment in a closed position showing two clamped conductors in section;

FIG. 5 is a sectional view taken along line v-v of FIG. 4; FIG. 6 is a sectional view along line VI-VI of FIG. 4;

FIG. 7 is a front elevational view of one part of the first embodiment in a closed position, showing two clamped conductors in section;

FIG. 8 is a sectional front elevational view of a second embodiment of the invention in a closed position, clamping two conductors;

FIG. 9 is a sectional view along line IXIX of FIG. 8; and

FIG. 10 is a front elevational view of one part of the second embodiment in an open position.

DESCRIPTION OF THE FIRST EMBODIMENT Turning now to FIG. 1, there is provided an upstanding central leaflike contact element 1 surrounded, in a substantially coplanar manner, by a resilient wire yoke 2. Both are securely held by their respective lower portions in an insulating support 3.

The opposed edges of the contact element 1 above the insulating support 3 are sharpened and comprise a first portion 1h, ih', respectively, which extend parallel to the legs of the wire yoke 2. The upper part 1c of the contact element I is tapered; there the sharpened second edge portions la and ib converge at an acute angle and terminate in a rounded head portion 1d.

As best seen in FIG. 7, the lower portion of the contact element 1 comprises a rectangular anchoring part 1e and an adjoining contact strip lg, both embedded in insulating support 3. As seen in FIG. 5, the anchoring part Ie of the contact member 1 is slightly offset with respect to its portions project ing beyond the insulating support 3 and, in its spaced openings 1f, receives a bent free end portion 2a of each leg of the yoke 2. The contact element 1 is a unitary stamped member preferably made of a copper alloy having good electrical conducting properties.

In order to establish the clamping connection according to the invention, insulated conductors 5 and 5' are introduced through the wire yoke 2 and are positioned in the relatively wide spaces a and [2, defined on the outside by a leg portion of the wire yoke 2 and, on the inside, by respective edges Ia, lb of the contact element 1. Instead of two conductors, a sole conductor 5 may be threaded through the wire yoke 2 and positioned in one of the spaces a or b as illustrated in FIG. I. The spaces a and b, respectively, continue as much narrower clamping gaps a and 12' (FIGS. 4 and 7), defined on the outside by a leg portion of the wire yoke 2 and, on the inside, by respective sharp edges 1h and 1h of the contact element 1.

As the successive step in establishing a clamping connection according to the invention, a removable pusher slide 4, forming part of the clip connector, is inserted on the precedingly described terminal element by causing the upper portion of both legs of yoke 2 to be engaged by the internal longitudinal channels 4a and 4b (FIGS. I and 6) of pusher slide 4.

Thereupon the pusher slide 4 is moved downwardly, forcing the conductors 5, 5' from spaces a and b into clamping gaps a and b, the width of each is smaller than the diameter of the wire conductor 5a.

As the conductors 5 and 5' are pressed into the slots a and b, the insulation of the conductors is, on the inside, progres sively cut through by the edges la and lb of the contact element 1 due to the slanted arrangement of said edges. On the outside, the insulation of the conductors is first pressed against the contacting portions of the wire yoke 2 and then pushed aside, baring the conductor wire. When the conductors 5, 5' assume the position shown in FIGS. 4 and 5 in the slot a and b, the sharp edges 1h, lh' of the contact element 1 have penetrated into the stripped conductor wires 50, 5a while, at their respective diametrically opposed outer side, the respective legs of circular cross section of the resilient yoke 2 are pressed into the wire, thus exerting a permanent contact pressure on the conductors. Preferably, the wire yoke 2 is made of spring steel or similar material.

The pusher slide 4, when in its lowermost position (FIGS. 2-5), partially surrounds with its channels 4a and 4b (FIG. 6) the respective legs of the yoke 2 on their outside. This immobilizes the legs of the yoke 2 by depriving them of the possibility of outwardly directed defonnation. The pusher slide 4 thus serves as a fixation member for the established clamping connection; it secures and even increases the contact pressure exerted by the resilient wire yoke 2 on the conductors 5, 5.

The pusher slide 4 is provided at its inner portion with a projecting tab 40 (FIGS. 1, 2, 4 and 5) which, in the closed terminal position of the pusher slide, snaps below the connecting portion 2b of the wire yoke 2, thus securely locking the pusher slide in place in its closed position.

The leading end of pusher slide 4 is provided with arcuate recesses 4e which, when the pusher slide is in its closed position, fonn substantially circular openings with complemental arcuate recesses 3a of insulating support 3. The insulated conductor, in front of and behind the electric clamping contact, is securely held in said circular openings in order to isolate from the clamping locations any external stresses to which the conductors 5, 5' may be exposed.

lt is seen from FIG. 3, showing two conductors 5 and 5 clamped into the clip connector, that these conductors are held entirely independent from one another. Thus, if only one of the conductors is to be replaced, such an operation in no manner affects the adjacently disposed conductor since the latter remains clamped in its respective clamping gap a or b.

DESCRIPTION OF THE SECOND EMBODIMENT Turning now to the embodiment depicted in FIGS. 8-10, there are provided two clamping contacts, one formed of a yoke 6, the other formed of a yoke 6', both made ofa material similar to that of yoke 2 of the first embodiment. The yokes 6, 6' are securely held by their lower portions in an insulating support 3', only schematically shown.

In this embodiment, insulated conductors 7, 7 are introduced into eyes c and d of the respective yokes 6, 6. Then the conductors 7, 7' are forced downward into the respective clamping gap c formed by parallel legs 6a and 6b of yoke 6 and into clamping gap d formed by parallel legs 60 and 6d of yoke 6' by pusher slide 4 in a manner similar to that described in connection with the first embodiment. During this operation the wire insulation is pushed aside and the legs 6a, 6b and 6c, 6d of circular section press against the respective bared conductor wire 7a and 7a (FIG. 9). Similarly to the first embodiment, a permanent contact pressure results.

As it may be seen from FIG. 9, the pusher slide 4, by means of its internal longitudinal channels 40 and 4b, is in sliding engagement with the two outermost legs 60 and 6c of yokes 6 and 6', respectively.

As it is apparent from FIG. 8, the pusher slide 4 is locked in place in its closed position by means of tab 40 in a manner identical to that of the first embodiment.

We claim:

1. A clip connector for insulated conductors comprising A. a terminal element having 1. an insulating support,

2. a bladelike contact element held in said insulating support and extending outwardly therefrom; said contact element including opposed sharpened edge portions,

. a resilient yoke held in said insulating support and surrounding said contact element substantially in the plane thereof; said resilient yoke having two legs each extending adjacent a sharpened edge portion; each leg with the adjacent edge portion defining a clamping gap each having a width smaller than the diameter of the conductor wire of said insulated conductor and B. a pusher slide cooperating with said terminal element and adapted to force a conductor into each clamping gap and adapted to assume a closed position on said terminal element about said resilient yoke.

2. A clip connector as defined in claim l, wherein said contact element is tapered beyond said two clamping gaps in a direction away from said insulating support.

3. A clip connector as defined "1 claim 1, wherein said contact element has an integral anchoring part extending into said insulating support and having openings adapted to receive the free end ofthe legs of said yoke. 

1. A clip connector for insulated conductors comprising A. a terminal element having
 1. an insulating support,
 2. a bladelike contact element held in said insulating support and extending outwardly therefrom; said contact element including opposed sharpened edge portions,
 3. a resilient yoke held in said insulating support and surrounding said contact element substantially in the plane thereof; said resilient yoke having two legs each extending adjacent a sharpened edge portion; each leg with the adjacent edge portion defining a clamping gap each having a width smaller than the diameter of the conductor wire of said insulated conductor and B. a pusher slide cooperating with said terminal element and adapted to force a conductor into each clamping gap and adapted to assume a closed position on said terminal element about said resilient yoke.
 2. a bladelike contact element held in said insulating support and extending outwardly therefrom; said contact element including opposed sharpened edge portions,
 2. A clip connector as defined in claim 1, wherein said contact element is tapered beyond said two clamping gaps in a direction away from said insulating support.
 3. A clip connector as defined in claim 1, wherein said contact element has an integral anchoring part extending into said insulating support and having openings adapted to receive the free end of the legs of said yoke.
 3. a resilient yoke held in said insulating support and surrounding said contact element substantially in the plane thereof; said resilient yoke having two legs each extending adjacent a sharpened edge portion; each leg with the adjacent edge portion defining a clamping gap each having a width smaller than the diameter of the conductor wire of said insulated conductor and B. a pusher slide cooperating with said terminal element and adapted to force a conductor into each clamping gap and adapted to assume a closed position on said terminal element about said resilient yoke. 